The notion that putting feelings into words has mental and physical health benefits is hardly new. When individuals experience chronic or acute distress, the act of seeing a therapist, talking with supportive others, or writing in a journal can each have substantial psychological benefits. Two decades of social and clinical psychological research on expressive writing1,2 have empirically documented that a small number of brief expressive writing sessions, focused on the source of one's distress can produce demonstrable mental and physical health benefits over the course of several months. Although a number of mechanisms have been proposed over the years, none have garnered widespread support. The current proposal suggests that putting feelings into words ("affect labeling") is a form of unintentional emotion regulation that serves to diminish distress by dampening limbic responses and the physiological correlates that typically parallel limbic activity. Affect labeling is associated with increased activity in right ventrolateral prefrontal cortex (RVLPFC), diminished amygdala activity, and diminished self-reported distress, similar to the pattern of effects observed during intentional emotion regulation. Additionally, it is proposed that intentional and unintentional emotion regulation both rely on a more general inhibitory control mechanism associated with RVLPFC. Thus, we will also examine whether common patterns of brain activation are associated with the performance of intentional and unintentional emotion regulation, as well as two other inhibitory control tasks from other domains (motor, social cognitive). Finally, neural responses on these tasks as well as results from an expressive writing procedure will be related to clinically-relevant individual difference variables (i.e., genes, personality, social history). All participants will participate in fMRI scans while performing the Affect Labeling &Emotion Regulation Task (ALERT), which assesses both intentional emotion regulation (using reappraisal) and unintentional emotion regulation (using affect labeling), as well as a motor inhibition task (i.e., go/no-go) and a social cognitive inhibition task (i.e., suppressing one's own perspective to appreciate another's differing perspective). Subsequently, participants will come in for four expressive writing sessions (or a control task in the control sample) and be assessed at 3 month follow-up for mental and physical health benefits. Putting feelings into words has demonstrated mental health benefits, yet the mechanism by which these benefits occur is poorly understood. The proposed research will be the first research to examine the neural bases of the benefits of expressive writing. This project will also examine whether inhibitory control in social, emotion, and motor domains rely on a common neurocognitive mechanism and whether individual differences in this mechanism relate to clinically-relevant variables (personality, social history, genes).